Former Vice President Joe Biden, calling the nation’s crumbling infrastructure a “disgrace,” on Friday urged a gathering of the New York City region’s planners to “sound the alarm” with President Donald Trump and the GOP-led Congress about the need for transportation upgrades.

Addressing a luncheon of the Regional Plan Association in Manhattan, Biden urged hundreds in the audience to push the federal government to fund trains, tunnels and other needed infrastructure.

“You need to start shouting about how bad things are,” said Biden, a longtime Amtrak rider. He said the region’s rails were “barely hanging on by a thread.”

Biden suggested that New Jersey Gov. Chris Christie, a Republican, should be in “purgatory” for his 2010 decision to forfeit billions in federal dollars to help build a rail tunnel under the Hudson River that transit advocates say is desperately needed.

Biden, a Democrat, criticized Christie’s decision to reject $3 billion in federal funds that essentially killed the $8.7 billion tunnel project, which would have meant a new two-track tunnel to midtown.

“The New Jersey governor, as my mother would say, God bless him in his infinite wisdom, shut the project down,” he said, calling those who rejected the money “stupid sons of guns.”

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“There’s always purgatory,” Biden said to laughter.

Biden made headlines in 2014 when he likened New York’s LaGuardia Airport to a third-world country’s.

To the chagrin of transit advocates, Christie axed the commuter rail tunnel, called Access to the Region’s Core, in 2010, citing cost overruns. Lamenting the state of the region’s transportation infrastructure, Biden said the tunnel would have been close to done by now.

A Christie representative could not be immediately reached for comment.

In just the last month, derailments at Penn Station have ruined commutes for hundreds of thousands of passengers, including an early April derailment that damaged a switch and track and halted service on 8 of 21 tracks. There was also a train stuck in a tunnel for almost three hours.

Christie’s decision left passengers with a century-old, storm-battered, and delay-prone tunnel belonging to Amtrak that Biden believes is moribund.

Christie supports a successor tunnel, called Gateway, but it’s unclear of the project’s fate under Trump.